Magnetic hard disk drives and other types of spinning media drives such as optical disk drives are well known. FIG. 1 illustrates an oblique view of a current hard disk drive and suspension. The disk drive unit 100 includes a spinning magnetic disk 101 containing a pattern of magnetic ones and zeroes on it that constitutes the data stored on the disk drive. The magnetic disk is driven by a drive motor (not shown). Disk drive unit 100 further includes a disk drive suspension 105 to which a magnetic head slider (not shown) is mounted proximate a distal end of load beam 107. The proximal end of a suspension or load beam is the end that is supported, i.e., the end nearest the base plate which is swaged or otherwise mounted to an actuator arm 103. The distal end of a suspension or load beam is the end that is opposite the proximal end, i.e., the distal end is the cantilevered end.
Suspension 105 is coupled to actuator arm 103, which in turn is coupled to a voice coil motor 112 that moves the suspension 105 arcuately in order to position the head slider over the correct data track on data disk 101. The head slider is carried on a gimbal which allows the slider to pitch and roll so that it follows the proper data track on the disk, allowing for such variations as vibrations of the disk, inertial events such as bumping, and irregularities in the disk's surface.
Both single stage actuated disk drive suspensions and dual stage actuated (DSA) suspension are known. In a single stage actuated suspension, only voice coil motor 112 moves suspension 105.
In a DSA suspension, in addition to voice coil motor 112 which moves the entire suspension, at least one microactuator is located on the suspension in order to effect fine movements of the magnetic head slider to keep it properly aligned over the data track on the spinning disk. The microactuator(s) provide much finer control and much higher bandwidth of the servo control loop than does the voice coil motor alone, which effects relatively coarse movements of the suspension and hence the magnetic head slider. A piezoelectric element, sometimes referred to simply as a PZT, is often used as the microactuator motor, although other types of microactuator motors are possible. In the discussion that follows, for simplicity the microactuator may be referred to simply as a “PZT” although it will be understood that the microactuator need not be of the PZT type.
FIG. 2 illustrates a top plan view of the prior art suspension 105 in FIG. 1. Two PZT microactuators 14 are affixed to suspension 105 on microactuator mounting shelves 18 that are an integral part of the load beam 107, such that the PZTs span respective gaps in base plate 11. Microactuators 14 are affixed to mounting shelves 18 by non-conductive epoxy 8 at each end of the microactuators. The positive and negative electrical connections can be made from the PZTs to the suspension's flexible wiring trace and/or to the grounded base plate by a variety of techniques.
There remains a continuing need for improved suspensions. Suspensions with enhanced performance capabilities are desired. The suspensions should be capable of being efficiently manufactured.